Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!cs.utexas.edu!uunet!cbmvax!daveh From: daveh@cbmvax.UUCP (Dave Haynie) Newsgroups: comp.sys.amiga Subject: Re: 1.4 ROMS? Message-ID: <7360@cbmvax.UUCP> Date: 19 Jul 89 17:08:23 GMT References: <460@aucis.UUCP> Organization: Commodore Technology, West Chester, PA Lines: 66 in article <460@aucis.UUCP>, easton@aucis.UUCP (Jeff Easton) says: > Summary: forget it, bizzare ROM's used > In article <19975@louie.udel.EDU>, new@udel.EDU (Darren New) writes: >> It also seems to me that under US Copyright law as I understand it, >> it sould be legal to burn your own proms from the kickstart that >> comes with the enhancer set... > I looked at this once (when 1.3 came out) and found it to be > near impossible to do economically. The only EPROMs we've used to date are EPROM towers, which hook up 4 32kx8 EPROMs (27512) to build a whole 128K x 16 equivalent. > First I whipped out my copy of the A500/A2000 technical reference > manual and checked the schematic. Hmm 128K x 16 ROM, P/N HN62402. > Sounds like a Hitachi part. A quick scan of my Hitachi data book shows > no such part. You may need a newer data book. We've bought there ROMs from several different vendors at different times, I think NEC makes 'em too, can't recall everyone but it seems to be pretty standard, at least as far as everyone in Japan is concerned. > OK, check the pinout with the Intel standard part. Bingo! there all WRONG! There was no EPROM available when these parts were specified. Methinks Intel did wrong by not following the existing standard. > The B2000 schematic shows all the data pins on the bottom half of the chip > and all address pins on the top half. The B2000 schematic is correct. > I posted a question about this many months ago but got no replys. > So how 'bout it guys? CATS? Dave? Why the weird part? To combat > theft? Or were you just to early (before the x16 standard was set)? Again, we used the only part available, which nowadays is still made and far as I know, pretty common. I tend to think the newer part is the one at fault, for not following the already established pinout. Or maybe it's just Intel thumbing its nose at Japan, Inc. Couldn't hurt to check and see if any of the other companies may a 128k x 16 EPROM; though as far as I know, they don't. > A daughter board could be devised to remap the pinout to a standard > for those inclined to mess with kickstart (noclick in ROM, etc) but > just wasnt worth it to me at the time. If there is a standard 128k x 16 EPROM, even if it needs a tower, it would sure be an easier solution than the 4-banger tower they're using now. > I would build one at the drop of a hat if I could kludge in some > code to get my old A2090 to autoboot. :< Think you'd need a 256k x 16 for that; there's no spare room in the current ROM for a hard disk driver. B2000s and A500 do support a large ROM, though hacking in a 2090 autoboot driver wouldn't be something I'd want to do without the source code... > Jeff Easton UUCP: !mailrus!sharkey!aucis!easton > Zenith Data Systems OEM Engineering. -- Dave Haynie Commodore-Amiga (Systems Engineering) "The Crew That Never Rests" {uunet|pyramid|rutgers}!cbmvax!daveh PLINK: D-DAVE H BIX: hazy Be careful what you wish for -- you just might get it